1. Field of the Invention
The present invention relates to an active air flap apparatus for a vehicle and a defect diagnosis method thereof, and more particularly, to a technology associated with an active air flap apparatus for a vehicle configured to respectively separate and diagnose a defect caused by a sensor and a defect caused by a mechanical connection mechanism.
2. Description of Related Art
FIGS. 1 and 2 illustrate one example of an active air flap apparatus for a vehicle in the related art. Therefore, the active air flap apparatus includes a duct housing 1 installed with being coupled to a front end module of the vehicle, an actuator 2 fixedly installed in the duct housing 1, a drive flap 4 directly connected with the actuator 2 through a drive shaft 3 and rotatably installed in the duct housing 1, and a driven flap 6 connected with the drive flap 4 through a link mechanism 5 and rotatably installed in the duct housing 1.
The actuator 2 includes a PCB 2a, a motor 2b, and a plurality of gear members 2c and is a structure in which one end of the drive shaft 3 is coupled to a final output gear 2d among the gear members 2c and further, a drive flap positional sensor 7 detecting a rotational angle of the drive flap 4 is mounted on the output gear 2d. 
Herein, as the drive flap positional sensor 7, a potentiometer may be used, but the drive flap positional sensor 7 is not limited thereto.
Accordingly, when the actuator 2 operates, power is transmitted through the drive shaft 3, and as a result the drive flap 4 rotates and rotational force of the drive flap 4 is transmitted to the driven flap 6 through the link mechanism 5, and as a result, the driven flap rotates together.
However, it is possible to verify the position of the drive flap 4 through the drive flap positional sensor 7, but it is impossible to verify the position of the rest of the driven flap 6 connected through the link mechanism 5, and as a result, when an error (a defect and a damage) occurs in the link mechanism 5, a state at that time cannot be diagnosed.
Further, the apparatus in the related art has only one sensor and does not have a diagnosis method for the defect of the sensor (drive flap positional sensor) itself and in particular, when the sensor is out of order, the air flap is misoperated by using a sensor value which is out of order.
In addition, the apparatus in the related art performs misdiagnosis due to a system defect even in a situation in which the flaps 4 and 6 are fixed by freezing or foreign materials.
The information disclosed in this Background of the Invention section is only for enhancement of understanding of the general background of the invention and should not be taken as an acknowledgement or any form of suggestion that this information forms the prior art already known to a person skilled in the art.